Mythbuster: How the inconsistent definition of click-through rates affects publishers and their advertisers

Mythbuster: How the inconsistent definition of click-through rates affects publishers and their advertisers

Email click-through rates would seem to be a simple metric for email service providers to calculate to help publishers and advertisers determine newsletter performance: Of the number of emails sent, what percentage of recipients clicked a link in the email.

But no. Instead, some email newsletter platforms report click-through rates (CTR) as click-to-open rates (CTOR), which are measured against the number of emails opened. However, three newsletter authors told Digiday the methodologies behind calculating CTR don’t really matter to them — or to their advertisers, who either have methods to verify the newsletter data themselves or rely on other metrics in tandem with CTR to determine where to buy ads in emails.

Why buyers prefer CTOR

Two media buyers told Digiday they’re aware newsletter platforms often calculate CTR based on open rates rather than on total email sends (even though Apple’s Mail Privacy Protection feature introduced last September has caused open rates to be viewed as unreliable).

Reporting CTOR as CTR in this way leads to a “higher” number that ESPs and newsletter authors can share with advertisers, Driggs said. “It looks better. So you would think [ESPs] would want to use that [number],” she said.

Driggs believes the industry needs to use standardized definitions for metrics like CTR and CTOR. “That would help prevent planners from using the wrong metrics against each other when comparing,” she said.

But it seems buyers actually prefer the way some ESPs are calculating CTR, by measuring clicks divided by opens — or “impressions,” said David Mirsky, group director at ad agency Crispin Porter + Bogusky — as opposed to total emails sent.

Continue reading this article on digiday.com.